Electrical ignition apparatus for internal-cobustion engines.



No. 796,849 PATENTED AUG. 1, 1906.

v A. J. POSTANS. ELECTRICAL IGNITION APPARATUS FOR. INTERNAL COMBUSTIONENGINES.

APPLICATION FILED OOT. 19,1903.

i'l l UNITED STATES PATENT OFFICE.

ARTHUR JAMES POSTANS, OF SOUTH KENSINGTON, ENGLAND.

ELECTRICAL IGNITION APPARATUS FOR INTERNAL-COMBUSTION ENGINES.

Specification of Letters Patent.

Patented Aug. 1, 1905.

Application filed October 19,1903. Serial No. 177,626.

To all whmn it may concern:

Be it known that I, ARTHUR J AMES POSTANS, engineer, a subject ofthe'King of Great Britain and Ireland, residing at 155 Fulham road,South Kensington, in the county of London, England, have inventedcertain new and use-' ful Improvements in Electrical Ignition Apparatusfor Internal-Combustion Engines, (for which I have applied for a patentin Great Britain, No. 9,305, dated April 24, 1903;) of which thefollowing is a specification.

This invention relates to an electrical ignition apparatus forinternal-combustion engines in which the spark produced on breaking asimple circuit of large inductance is used to ignite the combustiblemixture of the engine. To provide the spark required at the properinstant, the circuit includes two breaks, one of which is outside thecombustion-chamber and is normally open, while the other is inside thecombustion-chamber and is normally closed. IN hen the external break inthe circuit is closed, which may be done in any known manner by anyconvenient moving part of the engine, the current energizes a solenoidor solenoids or an. electromagnet or electromagnets included in thecircuit, and by means of the consequent attraction against the force ofa spring of a soft-iron armature attached to one of the contact-piecesof the internal break the latter is opened, and the sparkdue to theso-called extra current of the induction-circuit is produced and ignitesthe charge. A series of such sparks will take place during the time thatthe external break is closed. When there are two or more cylinders inthe engine and a single ignition-circuit, it would then be necessary toprovide additional independent external breaks, so as to avoidshort-circuiting the battery.

In the accompanying drawings, Figure 1 is an elevation of an ignitionapparatus constructed according to the present invention in which thefiring-circuit and external break are shown diagrammatically. Fig. 2 isa plan; Fig. 3, a sectional detail showing the arrangement of theinternal break, and Fig. 4a diagram showing an arrangement of theexternal breaks for a four-cylinder engine.

In the case of a single-cylinder engine the electric ignition-circuitincludes a suitable battery a, one terminal of which is in connectionwith one end of the inductance-coil 0 and the other through acircuit-closer Z), operated from any suitable moving part of the engine,with the ignition-plug f or any part in electric connection therewith.The other end of the coil, which preferably encircles a soft-iron core0, is connected to the spring-piece al, which is supported on butinsulated from a bracket 0, in which the coil is supported. Theignitionplug f, to one end of which the bracket 0 is attached by meansof the nut f is formed for screwing into the ignition-chamber in theusual way and has a central plug 9, of vulcanized fiber or othersuitable insulating material, through an axial hole, in which passes arod it, of hardened steel or other suitable material. On one end of therod is adjustably fixed a contact-piece h, which abuts against thespring (Z and is urged forward by it, so as normally to hold the otherend of the rod h in contact with the end of a bent rod 70, preferablyalso of hardened steel, which is screwed into the body of theignition-plug.

The armature of the electromagnet 0 consists of a soft iron or steel rodZ, journaled in the bracket 0 and having fixed at right angles to itsends and in the same plane with each other two bars or fingers Z ofsimilar material. These fingers are preferably long enough to reachbeyond the center of the iron core 0 and are normally held displaced toone side of the core by means of a spring m, fixed on the casing m,which incloses the coil, which engages with a reaction-piece n, fixed onthe rod Z, so as to permit the armature to oscillate on either side ofits normal position. The rod Z has also fixed to it a pin 0, whichprojects upward behind a collar 0 on an insulatingsleeve fixed on therod it.

WVhen the circuit-closer Z) is open, the sparking electrodes It 7c areheld in contact by the spring (Z; but as soon as the electromagnet isenergized by closing the switch Z the fingers Z of the armature areattracted toward the center of the core 0, thereby turning the rod Z inits bearings, so that the pin 0, pressing against the collar 0, forcesthe electrode it backward against the spring cZ and causes a break inthe circuit at the abutting ends of the electrodes h is, resulting in aspark at that point due to the so-called extra current. Theelectromagnet again becoming deenergized, the spring 17?. returns thearmature to its normal or unattracted position, and the spring CZ tendsto close, and if there has been no ignition of the charge in thecylinder will close the break at the electrodes h Z5, and theelectromagnet will again become energized if the switch Z is stillclosed. The time of contact of the circuit-closer Z2 can be variedwithinwide limits; but even the least time of contact obtainable by mechanicalmeans is long enough to produce a series of breaks and makes, andtherefore a series of sparks, at the electrodes hit. As soon, however,as the combustible mixture has been ignited the resulting pressure inthe cylinder forces the rod h outward against the reaction of the springd and holds the electrodes la 70 out of contact, at any rate long enoughto keep the circuit broken at h is, until it is again broken at theswitch 6.

The eccentric engagement of the pin 0 with the collar 0 causes thelatter, and with it the electrode h, to turn through a small angle eachtime the electromagnet is energized, and the regular wear of thesparking surface thus secured not only increases the life of theelectrodes, but also the certainty of their action.

When the same battery is used forthe igni tion-circuits of a number ofcylinders in which the ignition of the combustible mixture has to occursuccessively, the circuit-closers for the various circuits must bearranged so that the battery will not be short-circuited. Such acircuit-closer is illustrated diagrammatically in Fig. 4, which showssuch an arrangement of circuit for a four-cylinder explosionmotor. Oneelement 0 of each of the circuitclosers is connected to one of the polesof the battery a, and these elements are arranged to be successivelydisplaced by a moving part of the engine, so as to be brought intocontact with its fellow element g, each of which is connected to one endof its corresponding ind uctancecoil, the remainder of each of theseparate circuits being as shown in Fig. 1.

It is to be understood that the present invention is not to beconsidered to be limited to the construction herein described and illustrated, which may be varied in many ways as regards constructionaldetails without in any way'departing from the invention. 1

Having thus described the nature of this invention and the best means Iknow of carrying the same into practical effect, I claim 1. In apparatusof the kind herein described a movable sparking electrode, a collarattached to the electrode and a pin operated by an electromagnet adaptedto' engage eccentrically with the collar so as to move the electrodealong its axis and at the same time rotate it about its axis,substantially as and for the purpose specified.

2. An electrical igniter for explosion-engines comprising anelectromagnet, an armature adapted to be attracted thereby, a fixedelectrode and a movable electrode, means actuated by said armature forretracting the said movable electrode, and automatically-operating meansfor rotating the said movable electrode, substantially as and for thepurpose set forth.

3. An electrical igniter for explosion-engines comprising anelectromagnet, an armature adapted to be attracted thereby, a fixedelectrode and a slidable electrode, means actuated by said armature forretracting the said movable electrode, a spring adapted to retain thesaid armature in a normal position and a reaction-piece arranged to setthe said spring in any other than said normal position.

4. An electrical igniter comprising a sparking plug having a fixed and amovable electrode, means for closing the spark-gap when the pressure inthe combustion-chamber of.

the engine falls below a definite amount, and an electricallyoperateddevice engaging with said movable electrode for withd rawing it fromcontact with the fixed electrode, and simultaneously rotating it.

5. An electrical igniter comprisinga sparking plug having a fixed and aslidable electrode, said slidable electrode being rotatable and adaptedto contact with the fixed electrode, means for causing one of theelectrodes to contact with the other, an electrically-operated deviceengaging with said slidable electrode torotate the same whilewithdrawing it from contact with the fixed electrode, and means forclosing the spark-gap when pressure in the combustion-engine falls belowa definite amount.

In testimony whereofI have signed my name to this specification in thepresence of two subscribing witnesses.

ARTHUR JAMES POSTANS.

Witnesses:

OLIVER IMRAY, EDWARD GARDNER.

